BERLIN — The Austrian president called on Sunday for new elections in September after a tumultuous weekend during which the government collapsed over the emergence of a video that showed the country’s far-right vice chancellor promising favors to a woman who claimed to be a Russian investor.
The president, Alexander Van der Bellen, said his country had “exact rules and procedures” to handle the crisis that had ensued after Chancellor Sebastian Kurz said that he could no longer continue working with the Freedom Party, led by Vice Chancellor Heinz-Christian Strache.
Mr. Strache resigned on Saturday after the German newsmagazine Der Spiegel and the newspaper Süddeutsche Zeitung on Friday released the video, which was filmed months before the 2017 election, in which Mr. Kurz led his party to victory.
“Based on these constitutional rules, I will ensure stability, calm and continuity are of the highest priority,” Mr. Van der Bellen said in a statement after his meeting with Mr. Kurz. “Consequently, I urge there to be new elections in September, if possible at the beginning of the month,” the president added.
The downfall of Mr. Kurz’s right-leaning coalition government, just 17 months after taking office, fueled suspicions about how much far-right parties were willing to let Russia get involved in national politics.
The developments in Austria came a week before elections for the European Parliament, in which far-right movements across the Continent were poised to weaken support for more moderate and established parties.
Questions remain about how Mr. Kurz will be able to govern in the months until new national elections, with opposition figures and members of his own conservative People’s Party calling for all Freedom Party ministers to quit their posts. The most important of those is the interior minister, Herbert Kickl, who is responsible for the country’s security apparatus.
Pamela Rendi-Wagner, leader of the opposition Austrian Social Democrats, said in a statement to The New York Times that Mr. Kurz “had his chance and lost it.”
“Now he is not even able to ensure a stable transition,” she added. “As a first step, the three ministries of justice, interior and defense must immediately be filled with independent experts. It’s the only way to ensure a complete and independent investigation.”
Peter Filzmaier, an Austrian political scientist, told the public broadcaster ORF that everything was “up to the president,” adding that Mr. Van der Bellen “needs to name someone to take over the agenda of the vice chancellor.”
The video footage that was published by the German news outlets was filmed in a villa on the Spanish island of Ibiza three months before the 2017 Austrian elections in which Mr. Kurz led his party to victory.
It showed Mr. Strache promising infrastructure contracts to a woman who claimed to be the niece of a Russian oligarch in return for support for his Freedom Party and her offer to invest 250 million euros, around $280 million, in Austria. Mr. Strache also suggested undermining the independence of Austria’s news media. The New York Times could not independently verify the contents of the entire video.
The revelations followed a series of missteps by the Freedom Party since joining the coalition, and it raised fresh concerns about whether a party inside government had been working to undermine liberal democracy and press freedom in Austria.
Christoph Hofinger, the scientific director of the SORA research institute, which does election night forecasts, said that while the scandal would hurt the Freedom Party, it would not make the party irrelevant.
“I would be very surprised if they lost even half of their support,” Mr. Hofinger said. “But it’s likely they will lose votes,” he acknowledged.